1. Field of the Invention
The present invention relates to a belt curve conveyor used for changing direction of transportation of objects, and more particularly, to a belt curve conveyor comprising a fan-type belt detachably mounted on a body thereof.
2. Prior Art
In general, a belt curve conveyor is utilized to change the transporting direction of a belt conveyor for carrying objects.
In a conventional belt curve conveyor, in order to prevent a belt from being caught or deviated inside due to its tension, a marginal section is formed on the periphery of a fan-type belt in which a number of guide roller independently mounted on a guide bridge provided on the periphery of the belt in such a manner that those guide rollers pinch the ledge so as to maintain the tension against the outside of the fan-type belt. As a result, such a belt can not be exchanged or replaced easily.
This type of belt conveyor is replaced when necessity arises. In particular, when food or pharmaceuticals are transported, a belt is removed and cleaned on a regular basis to keep the whole conveyor line clean. For this purpose, a conventional belt in which a set of two guide rollers mounted vertically on upper and lower lines to prevent the belt from being deviated by supporting a thick part (projection) of the belt end, which allows the belt to be replaced easily, is common.
One example is shown in Japanese patent unexamined publication No. 2002-114343 (page 4, left column, line 33 to page 5, right column, line 31, and FIGS. 1 and 4). A cam is mounted on the upper part of an operation lever in which the lever is rotated in such a manner that the upper cam comes into a contact with a frame face as its first cam face changes to its second cam face so that an arm securing a guide roller on each side thereof is energized by a spring to spread in a suitable manner, and is extruded from the guide member to protrude forward so as to spread the arm so that the guide rollers come out from the thickest part (projection) of the belt end, which enables the belt to be replaced.
Problems to be Solved by the Invention
However, in a conventional belt curve conveyor, each of the guide rollers is secured to a fixed holder by a bolt engaged onto an inner surface of the guide roller through a bearing. When a belt is attached or removed, the fixed holder must be partially removed so as to remove both the guide rollers and the engaging means. As a result, a tool is required to remove a part of the fixed holder and remove the guide rollers with their engaging means. In addition, as the holder, rollers, and bolts are dismantled, it necessitates some time and labor to reinstall a fan-shaped belt after it has been disassembled and cleaned.
Furthermore, as shown in the prior art disclosed in the aforementioned publication, the thickest part of the belt end can be released by an operation lever to release guide rollers, which allows the belt to be pulled out on the internal diameter side. However, the energizing force to the extending direction of the upper and lower arms is weakened by being stored in the guide members for a long time so that it does not extend well when being protruded forward by the operation lever; as a result the thickest part (projection) of the belt end is caught by the lower guide roller as the belt sags down when it is pulled out to the fan shape on the internal diameter side, which eventually necessitates disassembly and removal of the guide rollers. As a further result, a tool is required to disassemble and remove a part of the fixed holder so as to remove the guide rollers and their engaging bolt, and to assemble them again. In addition, as the holder, rollers, and bolts are dismantled, it requires a certain amount of time and labor to reinstall a fan-shaped belt after it has been disassembled and cleaned.